Aim To investigate the protective effects of etomidate on cultured rat hippocampal neurons subjected to anoxia injury and its mechanism.Methods Hippocampal neurons of neonatal rat,which had been cultured in vitro for 10 days,were allocated to control groups and etomidate-treating groups.The neurons were exposed to oxygen-glucose deprivation for 24 h.The cell survival rate in each group was evaluated using MTT colorimetry.To explore the effect of etomidate on neuronal calcium overload evoked by anoxia or 50 mmol?L~(-1) KCl or 1 mmol?L~(-1) glutamate,fluo-3,a fluorescent probe,was used for imaging of intracellular calcium in laser scanning confocal microscope(LSCM)to measure real-time changes of [Ca~(2+)]_i in cultured rat hippocampal neurons.Results The hippocampal neurons developed acute neuronal swelling and widespread neuronal degeneration following anoxia for 24 h.Etomidate at concentrations of 1.2～4.8 mg?L~(-1) attenuated the neuronal injury in a dose-dependent manner(P

Objective To establish an in vitro oxygen-glucose deprivation/reoxygenation axon injury model in rat hippocampal neurons in order to found a basis for research concerning the injury of oxygen glucose deprivation and axons regeneration. MethodsThe hippocampal neurons isolated from rats 24 h after born and cultured for 7 d were exposed to D-hanks solution with nitrogen gas instead of the original culture medium for 0.5, 1.0 and 1.5 h respectively, and then continue to be cultured in the original culture medium with oxygen. LDH content in the culture media was measured at 1, 5, 24, 48 and 72 h after reoxygenation. The morphological changes of neuron and axon were observed with inverted phase contrast microscopy. ResultsAfter oxygen-glucose deprivation/reoxygenation injury, hippocampal neurons became darker, swollen, and were with shorten axons. With the elapse of time, the LDH content was increased. The survival rate of hippocampal neurons was higher and the change of axon length was more obvious in the group of oxygen-glucose deprivation for 0.5 h than in the other groups. ConclusionAn in vitro oxygen-glucose deprivation/reoxygenation axon injury model in rat hippocampal neurons is successfully established.

Scientific research training program is an important component in the 8-year medical education program. It focuses on the training of scientific research thinking and research methods. It is necessary to establish an effective evaluation system in order to achieve the learning outcomes of scientific research training program. PUMC has established an effective evaluation system which involves research project selecting,supervising,formative assessment,oral defense. This paper introduces the evaluation system of scientific research training program at PUMC.

Objective To investigate the effect of propofol on N-methyl-D-aspartate (NMDA) receptor-mediated currents. Methods Hippocampal neurons were prepared from newborn Wistar rats and cultured for 8-12 days. Whole cell currents were recorded using patch-clamp technique and cells were voltaged-clamped at - 80 mV. 100 ?mol?L-1 NMDA and 3 or 48 ?g?ml-1 propofol were applied with a multi-pipe ejection system. GABAA receptor was then blocked with 100 ?mol?L-1 bicuculline to investigate the effect of propofol on NMDA receptor without the influence of GABAA receptor.Results Run-down of INMDA induced by 100 ?mol?L-1 NMDA applied to neurons which were cultured for 8-12 days was 15%?8%. Propofol 3 or 48 ?g?ml-1 significantly inhibited spontaneous excitatory postsynaptic currents and elicited a Cl- -mediated response by direct activation of GABAA receptor in the absence of GABA. therefore produced a reversible inhibition of whole cell currents activated by NMDA. After the GABAA receptor was blocked by 100 ?mol?L-1 bicuculine propofol still inhibited NMDA currents slightly. Conclusion Propofol inhibits the NMDA subtype of glutamate receptor mainly through activation of GABAA receptor. It can also directly suppress the NMDA receptor slightly.

Objective To characterize the nasal resonance of children with spastic cerebral palsy by comparing it with that of ordinary school-age children.Methods The mean nasalance scores (MNSs) of 90 normal school-age children and 62 school-age children with spastic cerebral palsy were measured and compared.Results (1) Age has significant effects on the MNS of/a/,/i/and/m/ in ordinary children,but has almost no effect on the MNS of/u/.The MNS of/a/,/i/,/u/ and/m/ in children with spastic cerebral palsy does not change with age.(2) Sex only has a significant relationship with the MNS of/i/ in ordinary children,but does not significantly predict the other MNSs.(3) The MNS of/a/ of children with spastic cerebral palsy is significantly lower than that of ordinary children,and their MNS of/i/ and /u/ is significantly greater than those of ordinary children.Conclusions The MNS of /a/,/i/and /u/first increases and then decreases with age in ordinary children,while the MNS of/m/ increases gradually.Children with spastic cerebral palsy did not show the same trends and demonstrated a state of retardation of nasal resonance.Children with spastic cerebral palsy are more likely to display hypernasality than ordinary children.

Objective To establish an in vivo imaging method of normal or tumorous liver in mice by using a new type nanoparticle contrast agent, ExiTron nano 12000, coupled with micro-CT imaging.Methods Six 6-8-week old male C57BL/6J mice were randomly divided into group A and group group B, by intravenous injection of 50μL and 100μL Ex-iTron nano 12000, respectively.In vivo Micro-CT scans were performed before contrast agent injection, 3 minutes, 24 hours, 7, 14, 28 and 56 days after injection.To determine which dose is suitable for long-term studies, gray scale value a-nalysis was performed on selected region of interest ( ROI) in the left lobe and right anterior lobe of the liver, and the chan-ges of liver tissue contrast was monitored after ExiTron nano 12000 injection.Three male HBV transgenic mice bearing liver tumors ( group C) were intravenously injected with the determined dose of ExiTron nano 12000 and were monitored by mi-cro-CT scans as above described.At 56 days after ExiTron nano 12000 injection, the mice were sacrificed and liver sam-ples were taken for histological analysis.Results Cross-sectional images taken at various time points and the average gray scale value ( AGSV) analysis in the mouse liver revealed that the AGSV peaked at 24 hours after injection of contrast rea-gent and good contrast still presented in the livers within 56 days of observation for both groups, though group B showed a significantly higher contrast than group A (P＜0.01).Those data indicated that the dose of group B (100μL) was better to maintain ExiTron nano 12000 in the liver of mice for a long time.Contrast-enhanced by 100μL of ExiTron nano 12000, the liver tumor nodules in the mice of group C could be clearly delineated by Micro CT imaging during a 56 days observa-tion.Histological analysis revealed atypical hyperplasia, enlarged nuclei with hyperchromasia and cell necrosis in the tumors.Conclusions An in vivo imaging method was established to non-invasively visualize mouse liver using micro-CT combined with nanoparticle-based contrast agent and this technology may be applied to a live imaging of murine primary liv-er tumors.

BACKGROUND:Transgenosis of basic fibroblast growth factor (bFGF) gene has been successfully performed into the muscle satellite cells of rat extraocular muscles in the previous study of the research group, proving that bFGF could express in the myoblasts of extraocular muscles, also promote cell proliferation and differentiation.OBJECTIVE: To further investigate the methods for regulating the expression of the bFGF in myoblasts following transfection. METHODS: Target gene bFGF was connected with inducing expression vector pcDNA4/T0/myc-His?A, followed by masculine clone sequencing identified by colony PCR and enzyme digestion, EcoR I and Hind III restriction enzyme digestion, as well as Xho I single enzyme verification. C2C12 myoblasts antibiotics sensitivity was screened and finally defined. By use of lipofection transfection technology, cell lines where C2C12 stably expressed pcDNA6/TR were estabolishd and then identified by Western blot. The pcDNA4/TO/myc-His?A-bFGF was transfected into pcDNA6/TR- C2C12 cells. The bFGF expression and secretion in C2C12 cells following tetracycline-induced pcDNA4/TO/myc-His?A-bFGF transfection were determined by immunofluorescence and Western blot, the controls were established.RESULTS AND CONCLUSION: ① The conjunction between the bFGF and inducing expression vector pcDNA4/TO/myc-His?A was proved successfully by sequencing comparison, double digestion and single digestion. ②The minimal lethal concentration of blasticidin to C2C12 cells was 10 mg/L, while that of zeocin was 750 mg/L. ③ The pcDNA6/TR-C2C12 cell lines were established correctly. ④ The myoblasts treated by tetracycline and transfected with pcDNA4/TO/myc-His?A-bFGF were positive for gene expression, those untreated exhibited a negativity; bFGF protein could be produced in myoblasts treated by tetracycline and transfected with pcDNA4/TO/myc-His?A-bFGF, the production reached a peak at 24 hours, while those untreated can not produce bFGF protein. Results suggest that the bFGF expression in the myoblasts can be controlled by tetracycline inhibition and regulatory systems.

Objective To observe the effect of ischemic postconditioning on neuron structure plasticity and memory after global cerebral ischemia injury in rats and discuss the protection mechanism from aspect of Morphology. Methods A total of 36 SD male rats were randomly divided into sham operation group, global cerebral ischemia for 15 min group and global cerebral ischemia plus postconditioning group, 12 rats per group. The pullsinelli 4 vessel occlusion was applied to produce the models of global cerebral ischemia reperfusion injury, common carotid arteries (CCA) occlusion with 15 min and postconditioning with three cycles, of 15 sec release and 15 sec occlusion (15s/15s). Six rats from each group were evaluated by Morris Maze test for the ability of space learning and memory and the other six rats were evaluated by golgi stain for morphologic change of neuron. Results The ischemic postcondtioning group showed significant shorter mean escape latency compared with the sham operated group ( at day 3, P =0. 014; at day 4, P =0.040; at day 5, P =0.001 ). The density of dendritic spine in ischemic postcondtioning group was increased more significantly compared with ischemic group ( F = 562. 820,P ＜ 0. 01 ). Conclusion Ischemic postconditioning has obvious protective effect on cerebral ischemiainduced memory impairment, which may be related to alleviation of dendritic spine injury.

AIM: To explore the mechanism of nicotine against the apoptosis induced by colchicines in rat cortical neurons.METHODS: Cortical neurons were cultured from newborn Sprague-Dawley(SD) rats(less than 12 h).The rate of apoptosis was measured by Hoechst33258 fluorescence staining in the neurons,and the activity of Akt473 was analyzed by assay kit Akt473.RESULTS: The apoptosis of cortical neurons can be induced by 0.1 ?mol/L colchicine.The phosphorlation of Akt 473 decreased significantly(1/3 times of the control group,P

Aim To investigate the changes in the expression of protein kinase C gamma (PKC?), phosphorylated cAMP response element binding protein(pCREB)and immediate-early gene(c-fos and c-jun) in the spinal cord in formalin-induced inflammatory pain and study the effect of agmatine on the changes of PKC? activation, phosphorylation of CREB and expression of c-fos and c-jun.Methods Rats were decapitated at 10, 20 min or 2 h after intraplantar injection of 50 ?l 5% formalin and L_4, 5 spinal cords were dissected. Immunohistochemistry and western blotting analyses were used to observe the expression of PKC?, pCREB, c-fos and c-jun in the spinal dorsal horn and the effect of agmatine on the changes of their expression. Results Unilateral peripheral inflammation induced PKC? activation and CREB phosphorylation bilaterally while c-fos and c-jun expression ipsilaterally in rat spinal cord. PKC activity increased in membrane fractions with unchanged levels in the cytosolic fractions. Pretreatment intraperitoneally with 160 mg?kg-1 agmatine 15 min before inflammation significantly inhibited the activation of PKC? in the membrane fraction, suppressed the phosphorylation of CREB and the expression of c-fos and c-jun. Conclusion The mechanism of the analgesic effect of agmatine may be associated with inhibiting PKC? activation in the plasma membrane, CREB phosphorylation, c-fos and c-jun up-regulation which play roles in the hyperalgesia with peripheral inflammation.